CaCl2Backup

CaCl2Backup is a free, MIT-licensed backup mod for Minecraft Java servers using Fabric. It can create backups at intervals, on a daily schedule, or when the server stops, and those triggers can be combined. Backup files are written to temporary output, checked with full CRC verification, and published atomically after validation. Automatic cleanup can enforce both a maximum backup count and a maximum age. Operators can create, list, restore, and delete backups through /backup commands; all commands require OP privileges. Restoring replaces the current world save. The configuration can be reloaded without restarting the server. The changelog describes restore checks and recovery measures, including level.dat validation and rollback handling, and reports path-traversal and backup-name protections. To install it, first install Fabric Loader and Fabric API, then put the mod JAR in the server’s mods folder. The stated requirements are Minecraft 26.0+ in the 26.x series, Fabric Loader 0.15.0+, Fabric API, and Java 25+. Backups are stored locally, and restore granularity is a full backup.